This invention is related to fire-control sprinkler riser systems. More particularly, it is related to fire protection systems for connecting at least one water supply to at least one fire sprinkler system of a fire-protectable structure.
Typically, commercial buildings and an increasing number of residential structures are provided with fire suppression systems that dispense a fire suppression medium in the event of a fire. These fire sprinkler systems typically have a central pipe conduit from which a labyrinth of individual piping systems containing a fire suppression medium under pressure are attached.
In the event of a fire, sensors which are attached to the individual piping systems are activated thereby releasing the pressurized fire suppression medium in the hopes of quenching the fire. In many instances, the sudden release of system pressure activates a silent and/or audible alarm which alerts both those persons which are on the premises and the local fire authority that a fire is in progress.
Since typical fire suppression systems contain fluids under pressure, some means are needed to both check the integrity of the system against leakage and to provide for a means to alleviate system excess pressure in order to prevent catastrophic system rupture. In addition, a means is required to drain the system if the need arises and/or to quickly depressurize the system in order to check the integrity of the alarm.
Typically, the central pipe conduit is called a riser and is that small portion of a fire sprinkler system between a fire suppressant supply, typically water, and a fire suppressant outlet to fire sprinklers where the following components/functions are typically performed: a flow switch, to ascertain whether or not there is water flow in the riser pipe to the fire sprinkler system and to relay this information where needed (e.g., to fire departments); a test and drain valve, to open the riser pipe to a drain for the purposes of testing, bleeding, etc.; a pressure gauge, to deliver a read-out of the water pressure in the riser pipe; and a relief valve, to open the riser pipe to a drain in the event a certain (usually settable) water pressure is exceeded in the riser pipe. Typically, in plumbing fire-control sprinkler connections to a building water supply, the lower end of a riser pipe will be connected to a water supply pipe and the upper end will be connected to an outlet pipe to the sprinkler system, the riser pipe being stabilized in position by connecting it to the building structure, as by tying it to a beam.
To avoid doing the above as on-the-spot plumbing labor, it has been attempted for commercial uses to pre-make a steel, epoxy-coated riser manifold containing ports for the component attachments. Then such manifold, with or without components attached, may be plumbed on site for connection to a water inlet and sprinkler outlet. But there are still many unsolved problems, especially for residential uses where the sprinkler system is part of a drinkable water system. Manifolds for riser purposes, especially for residential risers, are not available with minimum lengths and costs, with efficient arrangement of ports and of pipe threads for component connection, with efficient means for supporting the riser in connecting to a structure, with abilities for safe and efficient use in all locations in any direction, etc.
Further, efficient riser port and component arrangements have not achieved their potentials in terms of improved structures, combined purpose lines, or combined purpose components. This is especially true in the areas of adapting plastics techniques in novel ways to such efficient riser, port, and component arrangements.
Additionally, flow switches are normally manufactured for connection plumbing by way of pipe threads, usually tapered pipe threads; however, there are many inefficiencies in such a connection. Eliminating such a connection would permit elimination of: an unnecessary joint which may be a point of current or future leakages; a large brass adapter fitting which is supplied with the flow switch for threaded pipe mounting; the use and need for thread sealing materials such as Teflon tape or pipe dope; the need for a large size wrench or pipe wrench (to tighten a 1″ N.P.T. tapered fitting requires a large amount of torque which in turn puts a great stress upon the entire manifold and pipe system—this stress could work loose the mounting brackets, screws, etc.); and the need to carefully orient the final positioning of the flow switch when rotating (tightening) the switch onto a threaded port for proper switch operation. Thus, a threaded attachment means, utilizing tapered pipe thread, provides a potential point of leakage, additional labor to assemble, unnecessary components and added cost. There is a need in the industry for an improved method and product for flow switch connection and for lower overall cost.
Even further, considering the fact that valves typically use springs in order to have pressure relief capability, a means is needed to insulate the valve spring from the system fluid in order to increase the useful life of the valve. To accomplish some of the above-mentioned valve requirements, typical fire suppression systems incorporate a multi-valve system which includes individual pressure relief valves, gate valves and lateral piping arrangements. Though these multi-valve systems are adequate to perform some of the above-mentioned requirements, they in turn require multiple components and a separate piping system necessitating an increase in expense and space requirements. Information relevant to attempts to address these problems can be found in, e.g., U.S. Pat. No. 5,662,139. However, the elongated handle described therein may be vulnerable to accidental movement. In addition, the relatively short travel distance along the cammed surface between the open and closed position may result in the “water hammer” effect which arises when a fluid flow through a piping system is suddenly terminated, thereby creating a reverberating pressure wave. And, in addition to other disadvantages, current such valves do not provide a means to insulate the spring from the system fluid. There exists a need for a new and improved fire-control system for use in fire suppression systems which provides for a choice between pressure test, pressure relief, and drain/test fluid flow capability, and which is less subject to accidental opening and closing and a system which is less prone to the creation of the water hammer effect. In addition, there exists a need for a means to insulate the spring from the system fluid in order to increase the useful life of the valve.
As described above, fire-control sprinkler systems are connected to a pressurized water supply. Further, such systems are typically connected using at least one fire control riser. Such fire control risers are typically connected between the pressurized water supply and the system of piping comprising the sprinkler heads. This invention relates to all such fire control risers, but more particularly to unitary risers of the type disclosed in the mentioned cross-references above.
Even further, the riser is generally installed prior to many types of construction activities, for example, application of gypsum board and painting. Often, extraneous construction materials come into contact with the riser or one of its components. There is a need to protect the riser from construction activities and extraneous materials. Also, for the foregoing reasons, there is a need for a fire-control sprinkler system with improved riser, component, and arrangement structures of the kind below described.